.jd_main {
  height: 50rem;
  min-width: 300px;
  max-width: 600px;
  position: relative;
  margin: 0 auto;
  .jd_header {
    position: fixed;
    left: 0;
    top: 0;
    height: 40px;
    width: 100%;
    .header_box {
      height: 40px;
      min-width: 300px;
      max-width: 600px;
      background-color: red;
      position: relative;
      margin: 0 auto;
      .icon_login{
        position: absolute;
        background-position: 0 -103px;
        width: 60px;
        height: 36px;
        display: block;
        top:4px;
        left: 10px;
      }

      form{
        width: 100%;
        height: 40px;
        padding-left: 75px;
        padding-right: 55px;
        position: relative;
        .icon_search{
          position: absolute;
          background-position:-60px -109px;
          width: 20px;
          height: 20px;
          display: block;
          top:10px;
          left: 85px;
        }
        input{
          width: 100%;
          height: 30px;
          border-radius: 15px;
          margin-top: 5px;
          padding-left: 40px;
        }

      }
      .login{
        position: absolute;
        width: 50px;
        height: 40px;
        top:0;
        right: 0;
        color: #ffffff;
        display: block;

        text-align: center;
        line-height: 40px;
        font-size: 15px;
      }
    }
  }

  .jd_banner{
    width: 100%;
    overflow: hidden;
    position: relative;
    ul{
      width: 100%;
      float: left;
      display: block;
    }
  }
}

.jd_nav{
  height: 169px;
  width: 100%;
  border-bottom: 1px solid #c0c0c0;
  padding: 0 3.125%;
  ul{
    width: 100%;
    margin-top: 10px;
    li{
      width: 25%;
      height: 69px;
      float: left;
      a{
        display: block;
        width: 100%;
        height: 100%;
        text-align: center;
       img{
         height: 40px;
         width: 40px;
         display: block;
         margin: 0 auto;
         p{
           font-size: 12px;
           color: #666;
         }
        }
      }
    }
  }


}

[class^="icon_"]{
  background:url("../images/sprites.png") no-repeat;
  background-size: 200px 200px;
}